A roller coaster (370 kg) moves from A (5.00 m above the ground) to B (25.0 m above the ground). Two nonconservative forces are present: friction does -2.00 x 10^4 J of work on the car, and a chain mechanism does +3.00 x 10^4 J of work to help the car up a long climb. What is the change in the car's kinetic energy, ?KE = KEf - KE0, from A to B?